Abstract. In the context of Brans-Dicke theory, we have found that primordial black holes can be formed in the matter-dominated era. Considering an early matter-dominated era between inflation and reheating, we show that the primordial black holes formed during that era evaporate quicker than those of early radiation-dominated era. Thus, in comparison with latter case, less number of primordial black holes could exist today. Again the constraints on primordial black hole formation become stronger than their radiation-dominated era counterparts indicating a significant enhancement in the formation of primordial black holes during the matter-dominated era.